Created for Professor Brian LaPointe to illustrate main concepts in his recent paper on the changing ratio of biologically available Nitrogen (DIN) and Phosphorus (SRP) as well as ratios of total nitrogen:phosphorus on the state of the nearshore ecosystem. One thing Brian wanted me to convey was the onshore anthropogenic drivers of the DIN:SRP and N:P changes - heavy build up of homes, primarily with septic systems, reduction in vegetative buffer zones than can absorb runoff and nutrients, and insufficient municipal water treatment plants.

Long and short: Increased load of DIN (and especially ammonia) and N relative SRP and P causes algae to begin to dominate waters starting with single celled algae that can quickly respond to nutrient change. These algal cell concentrations limit light penetration (Kd) of water column causing reduced diversity and biomass of sea grasses, macro algae, corals and sponges. At sufficient numbers algae cause die offs of fish and other organisms as they decompose at depth smothering some organisms under a layer of dead cells, and removing large amounts of oxygen from the water column.